Function and Biology

Human alpha-galactosidase catalytic mechanism 1. Empty active site

Source organism: Homo sapiens

EC 3.2.1.22: Alpha-galactosidase

Reaction catalysed:
Hydrolysis of terminal, non-reducing alpha-D-galactose residues in alpha-D-galactosides, including galactose oligosaccharides, galactomannans and galactolipids
Systematic name:
Alpha-D-galactoside galactohydrolase
Alternative Name(s):
  • Alpha-D-galactosidase
  • Alpha-galactosidase A
  • Alpha-galactoside galactohydrolase
  • Melibiase

Sequence families

Pfam Protein families (Pfam)
PF17450
Domain description: Alpha galactosidase A C-terminal beta sandwich domain
Occurring in:
  1. Alpha-galactosidase A
The deposited structure of PDB entry 3hg2 contains 2 copies of Pfam domain PF17450 (Alpha galactosidase A C-terminal beta sandwich domain) in Alpha-galactosidase A. Showing 1 copy in chain B.

PF16499
Domain description: Alpha galactosidase A
Occurring in:
  1. Alpha-galactosidase A
The deposited structure of PDB entry 3hg2 contains 2 copies of Pfam domain PF16499 (Alpha galactosidase A) in Alpha-galactosidase A. Showing 1 copy in chain B.

InterPro InterPro annotations
IPR002241
Domain description: Glycoside hydrolase, family 27
Occurring in:
  1. Alpha-galactosidase A
IPR035373
Domain description: Alpha galactosidase A, C-terminal beta-sandwich domain
Occurring in:
  1. Alpha-galactosidase A
IPR013780
Domain description: Glycosyl hydrolase, all-beta
Occurring in:
  1. Alpha-galactosidase A
IPR000111
Domain description: Glycoside hydrolase family 27/36, conserved site
Occurring in:
  1. Alpha-galactosidase A
IPR017853
Domain description: Glycoside hydrolase superfamily
Occurring in:
  1. Alpha-galactosidase A
IPR013785
Domain description: Aldolase-type TIM barrel
Occurring in:
  1. Alpha-galactosidase A

Structure domains

CATH CATH domains
2.60.40.1180
Class: Mainly Beta
Architecture: Sandwich
Topology: Immunoglobulin-like
Homology: Golgi alpha-mannosidase II
Occurring in:
  1. Alpha-galactosidase A
The deposited structure of PDB entry 3hg2 contains 2 copies of CATH domain 2.60.40.1180 (Immunoglobulin-like) in Alpha-galactosidase A. Showing 1 copy in chain B.
3.20.20.70
Class: Alpha Beta
Architecture: Alpha-Beta Barrel
Topology: TIM Barrel
Homology: Aldolase class I
Occurring in:
  1. Alpha-galactosidase A
The deposited structure of PDB entry 3hg2 contains 2 copies of CATH domain 3.20.20.70 (TIM Barrel) in Alpha-galactosidase A. Showing 1 copy in chain B.